While baleing my 560 diesel started to make grinding gear noise when clutching in the pto. holding foot clutch untill the tranny stopped spinning gears had no effect. did not always do it. but at least 75% of the time. It would eventually engage and run the baler.
My IT manual doesnt show any gears between the pto clutch and the output shaft. And i understand that the path is engine shaft turning, pto clutch, pto shaft out the back. no gear shifting involved.
It looks like there are drive gears concentric on the pto shaft as part of the tranny, but holdng the clutch should stop all tranny gear spin.
?????????/

So far i have determined that the pto is the middle version. 3 are planetary, clutch and clutch with adjustment port.
Also on another locatin, advice is to just adjust the pto clutch and brake per the book.

entire pto assembly is abut the size of a cr battery.
I have not done it yet as i have been redesigning the bale shooter on new holland 273.
I still am curious abut the gear grinding sound when engaging.

The book doesnt say so , but drain the transmission before messing with the pto.
Also put the pto in drive position, (over center) before removing. Or you need a huge vice to hold it while trying to shift it with a 3 foot pipe on the shift arm.
When re-installing,
Its difficult to impossible to re-align and insert the outer clutch part of the pto with the inner drive cup and pilot bearing. Easy to do on the floor.
re placeing the whole assembly and aligning the inner driveshaft was about 2 minutes.
If the inner part comes out part way or too far you will dump 10 gallons of oil on your feet. (a pair of shoes and 5 bags of oil dry and $80 worth of oil)
Also a good time to clean out the rear housing. sludge and steel shavings etc.
I also put a fairly large magnet on the bottom of the space between the bull
gears.
now to test..

So far I have baled about 400 bales, No more noise from shifting the PTO
in gear. Maybe new oil and some re-alignment while re-installing has stopped the inner most gear from catching on a transmission gear.
?????
Can't argue with success.